The lack of community at Webtoons seems to be by design. It's simply exists to publish popular Naver webtoons in English plus it offers English language webcomics.
It doesn't mean there isn't a fandom for those comics. In Korea, the fans simply go to a Naver hosted net cafe (forum), the address is often at the end of the webtoon chapter and comment there sometimes and the creator replies to them. However, LINE webtoons doesn't seem to have that option. You pretty have to figure how to go round to building community for your comic.
The lack of PR at LINE webtoons is really odd. Spottoon is another sire that also hosts Korean webtoons in English but they do have someone that answers reader questions.